Investigation on femtosecond laser irradiation energy in inducing hydrophobic polymer surfaces

► Ultrashort femtosecond laser pulses can induce hydrophobic properties on PMMA surfaces. ► The wettability modification depends on the laser energy deposition. ► A simple equation deduced from the laser parameters can express the energy deposition. ► Water contact angle exceeds 120° with a maximum of around 125° at the energy deposition range 600-900 J/cm2.